History of depression as a risk factor for dementia: an updated review

Food insecurity and low self-efficacy are associated with health care access barriers among Puerto-Ricans with type 2 diabetes

Racial/ethnic minorities are disproportionately affected by barriers to health care access and utilization. The primary objective was to test for an independent association between household food insecurity and health care access/utilization. In this cross-sectional survey, 211 Latinos (predominantly, Puerto-Ricans) with type 2 diabetes (T2D) were interviewed at their homes. Factor analyses identified four barriers for health care access/utilization: enabling factor, doctor access, medication access and forgetfulness. Multivariate logistic regression models examined the association between each of the barrier factors and food insecurity controlling for sociodemographic, cultural, psychosocial, and diabetes self-care variables. Higher food insecurity score was a risk factor for experiencing enabling factor (OR = 1.46; 95% CI = 1.17-1.82), medication access (OR = 1.26; 95 CI% = 1.06-1.50), and forgetfulness (OR = 1.22; 95 CI% = 1.04-1.43) barriers. Higher diabetes management self-efficacy was protective against all four barriers. Other variables associated with one or more barriers were health insurance, perceived health, depression, blood glucose, age and education. Findings suggest that addressing barriers such as food insecurity, low self-efficacy, lack of health insurance, and depression could potentially result in better health care access and utilization among low income Puerto-Ricans with T2D.

Risk of dementia in patients with insomnia and long-term use of hypnotics: a population-based retrospective cohort study

BACKGROUND

Hypnotics have been reported to be associated with dementia. However, the relationship between insomnia, hypnotics and dementia is still controversial. We sought to examine the risk of dementia in patients with long-term insomnia and the contribution of hypnotics.

METHODS

Data was collected from Taiwan's Longitudinal Health Insurance Database. The study cohort comprised all patients aged 50 years or older with a first diagnosis of insomnia from 2002 to 2007. The comparison cohort consisted of randomly selected patients matched by age and gender. Each patient was individually tracked for 3 years from their insomnia index date to identify whether the patient had a first diagnosis of dementia. Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

We identified 5693 subjects with long-term insomnia and 28,465 individuals without. After adjusting for hypertension, diabetes mellitus, hyperlipidemia, and stroke, those with long-term insomnia had significantly higher risks of dementia (HR, 2.34; 95% CI, 1.92-2.85). Patients with long-term insomnia and aged 50 to 65 years had a higher increased risk of dementia (HR, 5.22; 95% CI, 2.62-10.41) than those older than 65 years (HR, 2.33; 95% CI, 1.90-2.88). The use of hypnotics with a longer half-life and at a higher prescribed dose predicted a greater increased risk of dementia.

CONCLUSIONS

Patients with long-term use of hypnotics have more than a 2-fold increased risk of dementia, especially those aged 50 to 65 years. In addition, the dosage and half-lives of the hypnotics used should be considered, because greater exposure to these medications leads to a higher risk of developing dementia.

Depression and the risk for dementia

PURPOSE OF REVIEW

Depression is associated with increased risk of subsequent development of dementia; however, the nature of the association is still poorly understood. The purpose of the review was based on recent studies to discuss whether depression is a prodromal state of dementia or an independent risk factor for dementia, as well as to discuss how the type of depression, the type of dementia, and antidepressant treatment influence the association.

RECENT FINDINGS

Findings from recent studies suggest that some forms of depressive illness, for example early-onset depression before age 65 years and recurrent depression, may constitute long-term risk factors for development of dementia, whereas the onset of more recent depressive symptoms may reflect a prodromal phase of dementia. It is not clear whether specific subtypes of depression correspond to specific types of dementia. Recent studies suggest that long-term treatment with antidepressants may decrease the risk of developing some types of dementia, depending on the type of depressive disorder.

SUMMARY

This review has shown that the type of depression and dementia, as well as the effect of drug treatment, has to be considered to improve knowledge on the association between depression and dementia.

History of depression prior to Alzheimer's disease and vascular dementia verified post-mortem

The aim of this study was to analyze the medical history, with regards to previous remote depression, in patients with neuropathologically verified Alzheimer's disease (AD), vascular dementia (VaD) and mixed AD/VaD. The 201 patients included (115 AD, 44 VaD and 42 mixed AD/VaD) had been referred to the Psychogeriatric/Psychiatric Department, Lund University Hospital, for psychogeriatric investigation and were followed-up with clinical records and detailed information on psychiatric history prior to the onset of dementia. Depression was considered to exist when the patient had consulted a psychiatrist or physician and had been diagnosed with a "depressive episode" or "depression" and when anti-depressants and/or other specific treatments had been prescribed. Twenty patients (10%) had suffered from depression earlier in life well before the onset of dementia. Eight of the 9 AD patients with a previous diagnosis of depression had suffered from only one depressive episode and all had responded well to treatment, with complete recovery. In the VaD group, 8 out of 9 patients suffered two or more depressive episodes and only two recovered completely. Events with a possible significant relationship to depression were seen in 8 of the 9 AD patients but in only 1 of the 9 VaD patients. Psychotic symptoms were more common in VaD than in the AD group. The treatment modality of depression was similar in the groups. In conclusion, a history of depression prior to dementia is more common and more therapy-resistant in VaD than in AD.

Four-year outcome of mild cognitive impairment: the contribution of executive dysfunction

OBJECTIVE

The contribution of executive cognition (EC) to the prediction of incident dementia remains unclear. This prospective study examined the predictive value of EC for subsequent cognitive decline in persons with mild cognitive impairment (MCI) over a 4-year period.

METHOD

One hundred forty-one persons with MCI (amnestic and nonamnestic, single- and multiple-domain) received a baseline and two biennial follow-up assessments. Eighteen tests, assessing six different aspects of EC, were administered at baseline and at 2-year follow-up, together with screening cognitive and daily functioning measures. Longitudinal logistic regression models and generalized estimating equations (GEE) were used to examine whether EC could predict progression to a Clinical Dementia Rating Scale (CDR; C. P. Hughes, L. Berg, W. L. Danziger, L. A. Coben, & R. L. Martin, 1982, A new clinical scale for the staging of dementia, British Journal of Psychiatry, Vol. 140, pp. 566-572) score of 1 or more over the 4-year period, first at the univariate level and then in the context of demographic and clinical characteristics, daily functioning measures, and other neurocognitive factors.

RESULTS

Over the 4-year period, 56% of MCI patients remained stable, 35% progressed to CDR ≥ 1, and 8% reverted to normal (CDR = 0). Amnestic MCI subtypes were not associated with higher rates of progression to dementia, whereas subtypes with multiple impairments were so associated. Eight out of the 18 EC measures, including all three measures assessing inhibition of prepotent responses, predicted MCI outcome at the univariate level. However, the multivariate GEE model indicated that age, daily functioning, and overall cognitive functioning best predicted progression to dementia.

CONCLUSION

Measures of EC (i.e., inhibitory control) are associated with MCI outcome. However, age and global measures of cognitive and functional impairment are better predictors of incident dementia.

Depressive symptoms and memory performance among older adults: results from the ACTIVE memory training intervention

BACKGROUND

Cognitive performance benefits from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study may differ for individuals who exhibit a greater number of depressive symptoms.

METHOD

Using data from ACTIVE memory training and control conditions, we evaluated the effect of depressive symptomatology on memory scores across a 5-year period. Of 1,401 participants, 210 had elevated depressive symptoms at baseline, as measured by a 12-item version of the Center for Epidemiological Studies-Depression Scale (CES-D).

RESULTS

Participants with elevated depressive symptoms scored significantly lower at baseline and had faster decline in memory performance than those exhibiting fewer depressive symptoms. Memory score differences among depressive symptom categories did not differ between training conditions.

DISCUSSION

Findings suggest that elevated depressive symptoms may predict declines in memory ability over time, but do not attenuate gains from training. Training provides a potential method of improving memory which is robust to effects of depression.

Depressive symptoms, antidepressant use, and brain volumes on MRI in a population-based cohort of old persons without dementia

We examined whether late-life depression, including depressive symptoms and antidepressant use, was associated with smaller total brain volume, smaller hippocampal volume, and larger white matter hyperintensity (WMH) volume in a large community-based cohort of old persons without dementia. Within the Washington/Hamilton Height-Inwood Columbia Aging Project (WHICAP), a community-based cohort study in northern Manhattan, 630 persons without dementia (mean age 80 years, SD = 5) had volumetric measures of the total brain, hippocampus, and WMH at 1.5 Tesla MRI and data on current depression, defined as a score of 4 or higher on the 10-item Center for Epidemiologic Studies-Depression (CES-D) scale, or use of antidepressants. Multiple linear regression analyses adjusted for age, gender, ethnicity, education, cardiovascular disease history, and MRI parameters showed that subjects with current depression had smaller relative total brain volume (B = -0.86%; 95% CI -1.68 to -0.05%; p < 0.05), smaller relative hippocampal volume (B = -0.07 ml; 95% CI -0.14 to 0.00 ml; p = 0.05), and larger relative WMH volume (natural logtransformed B = 0.19 ml; 95% CI 0.02 to 0.35 ml; p < 0.05). When examined separately, antidepressant use was significantly associated with smaller total brain, smaller hippocampal, and larger WMH volume, while high CES-D scores were not significantly associated with any of the brain measures, although the direction of association was similar as for antidepressant use. With the caveat that analyses were cross-sectional and we had no formal diagnosis of depression, our findings suggest that in this community-based sample of old persons without dementia, late-life depression is associated with more brain atrophy and more white matter lesions, which was mainly driven by antidepressant use.

Dysthymia and depression increase risk of dementia and mortality among older veterans

OBJECTIVE

To determine whether less severe depression spectrum diagnoses such as dysthymia, as well as depression, are associated with risk of developing dementia and mortality in a "real-world" setting.

DESIGN

Retrospective cohort study conducted using the Department of Veterans Affairs (VA) National Patient Care Database (1997-2007).

SETTING

VA medical centers in the United States.

PARTICIPANTS

A total of 281,540 veterans aged 55 years and older without dementia at study baseline (1997-2000).

MEASUREMENTS

Depression status and incident dementia were ascertained from International Classification of Diseases, Ninth Revision codes during study baseline (1997-2000) and follow-up (2001-2007), respectively. Mortality was ascertained by time of death dates in the VA Vital Status File.

RESULTS

Ten percent of veterans had baseline diagnosis of depression and nearly 1% had dysthymia. The unadjusted incidence of dementia was 11.2% in veterans with depression, 10.2% with dysthymia and 6.4% with neither. After adjusting for demographics and comorbidities, patients diagnosed with dysthymia or depression were twice as likely to develop incident dementia compared with those with no dysthymia/depression (adjusted dysthymia hazard ratio [HR]: 1.96, 95% confidence interval [CI]: 1.71-2.25; and depression HR: 2.18, 95% CI: 2.08-2.28). Dysthymia and depression also were associated with increased risk of death (31.6% dysthymia and 32.9% depression versus 28.5% neither; adjusted dysthymia HR: 1.41, 95% CI: 1.31-1.53; and depression HR: 1.47, 95% CI: 1.43-1.51).

CONCLUSIONS

Findings suggest that older adults with dysthymia or depression need to be monitored closely for adverse outcomes. Future studies should determine whether treatment of depression spectrum disorders may reduce risk of these outcomes.

Systematic reviews on behavioural and psychological symptoms in the older or demented population

Introduction

Behavioural and psychological symptoms of dementia (BPS) include depressive symptoms, anxiety, apathy, sleep problems, irritability, psychosis, wandering, elation and agitation, and are common in the non-demented and demented population.

Methods

We have undertaken a systematic review of reviews to give a broad overview of the prevalence, course, biological and psychosocial associations, care and outcomes of BPS in the older or demented population, and highlight limitations and gaps in existing research. Embase and Medline were searched for systematic reviews using search terms for BPS, dementia and ageing.

Results

Thirty-six reviews were identified. Most investigated the prevalence or course of symptoms, while few reviewed the effects of BPS on outcomes and care. BPS were found to occur in non-demented, cognitively impaired and demented people, but reported estimates vary widely. Biological factors associated with BPS in dementia include genetic factors, homocysteine levels and vascular changes. Psychosocial factors increase risk of BPS; however, across studies and between symptoms findings are inconsistent. BPS have been associated with burden of care, caregiver's general health and caregiver depression scores, but findings are limited regarding institutionalisation, quality of life and disease outcome.

Conclusions

Limitations of reviews include a lack of high quality reviews, particularly of BPS other than depression. Limitations of original studies include heterogeneity in study design particularly related to measurement of BPS, level of cognitive impairment, population characteristics and participant recruitment. It is our recommendation that more high quality reviews, including all BPS, and longitudinal studies with larger sample sizes that use frequently cited instruments to measure BPS are undertaken. A better understanding of the risk factors and course of BPS will inform prevention, treatment and management and possibly improve quality of life for the patients and their carers.

Survival of patients with incident dementia who had a pre-existing psychiatric disorder: a population-based 7-year follow-up study

OBJECTIVES

Although it is widely accepted that psychiatric disorders and dementia coexist and survival data for dementia patients have been published, there is a paucity of information regarding the survival of patients with a psychiatric disorder who develop dementia. This study fills this information gap providing survival data on patients with such comorbidity and identifies mortality risk factors.

METHODS

All residents of Saskatchewan, a Canadian province, diagnosed with psychiatric problems and/or dispensed a psychiatric drug in 2000 and without dementia were followed through to 31 December 2006; the development of incident dementia was noted. Median survival time (in months) and selected predictors of mortality were measured. Analyses used Cox's proportional hazard model. Incidence density of dementia for the year 2000 was also computed.

RESULTS

By December 2006, 5,583 subjects with psychiatric disorders in 2000 had been diagnosed with incident dementia, and 60.65% of them died. Dementia-incidence density in this population for 2000 was 0.01 per 1000 person years at risk among those aged 18-64 years and rapidly increased to 3.13 per 1000 person years at risk among those aged 75 to 84 years. The median survival time from dementia onset to death was 32.66 months (interquartile range 31.21-34.14). Being male, later age of onset of dementia, having a lower income, and a high chronic disease score predicted shorter survival.

CONCLUSIONS

The comorbidity of psychiatric disorders and dementia resulted in shorter survival compared with that reported for patients with dementia only. These findings can be used for prognosis for patients, caregivers, and service providers.

Midlife vs late-life depressive symptoms and risk of dementia: differential effects for Alzheimer disease and vascular dementia

CONTEXT

Depression and dementia are common in older adults and often co-occur, but it is unclear whether depression is an etiologic risk factor for dementia.

OBJECTIVE

To clarify the timing and nature of the association between depression and dementia.

DESIGN

We examined depressive symptoms assessed in midlife (1964-1973) and late life (1994-2000) and the risks of dementia, Alzheimer disease (AD), and vascular dementia (VaD) (2003-2009) in a retrospective cohort study. Depressive symptoms were categorized as none, midlife only, late life only, or both. Cox proportional hazards models (age as timescale) adjusted for demographics and medical comorbidities were used to examine depressive symptom category and risk of dementia, AD, or VaD.

SETTING

Kaiser Permanente Medical Care Program of Northern California.

PARTICIPANTS

Thirteen thousand five hundred thirty-five long-term Kaiser Permanente members.

MAIN OUTCOME MEASURE

Any medical record diagnosis of dementia or neurology clinic diagnosis of AD or VaD.

RESULTS

Subjects had a mean (SD) age of 81.1 (4.5) years in 2003, 57.9% were women, and 24.2% were nonwhite. Depressive symptoms were present in 14.1% of subjects in midlife only, 9.2% in late life only, and 4.2% in both. During 6 years of follow-up, 22.5% were diagnosed with dementia (5.5% with AD and 2.3% with VaD). The adjusted hazard of dementia was increased by approximately 20% for midlife depressive symptoms only (hazard ratio, 1.19 [95% CI, 1.07-1.32]), 70% for late-life symptoms only (1.72 [1.54-1.92]), and 80% for both (1.77 [1.52-2.06]). When we examined AD and VaD separately, subjects with late-life depressive symptoms only had a 2-fold increase in AD risk (hazard ratio, 2.06 [95% CI, 1.67-2.55]), whereas subjects with midlife and late-life symptoms had more than a 3-fold increase in VaD risk (3.51 [2.44-5.05]).

CONCLUSIONS

Depressive symptoms in midlife or in late life are associated with an increased risk of developing dementia. Depression that begins in late life may be part of the AD prodrome, while recurrent depression may be etiologically associated with increased risk of VaD.

Prevalence of dementia and its correlates among participants in the National Early Dementia Detection Program during 2006-2009

OBJECTIVE

To investigate the prevalence of dementia and its correlates among people with poor socioeconomic status, poor social support systems, and poor performance on the Korean version of the Mini-Mental Status Exam (MMSE-KC).

METHODS

We used 2006-2009 data of the National Early Dementia Detection Program (NEDDP) conducted on Jeju Island. This program included all residents >65 years old who were receiving financial assistance. We examined those who performed poorly (standard deviation from the norm of <-1.5) on the MMSE-KC administered as part of the NEDDP, using age-, gender-, and education-adjusted norms for Korean elders. A total of 1708 people were included in this category.

RESULTS

The prevalence of dementia in this group was 20.5%. Multivariate logistic regression analysis revealed that the following factors were statistically significantly associated with dementia: age of 80 or older, no education, nursing home residence, and depression.

CONCLUSION

The prevalence of dementia is very high among those with lower MMSE-KC scores, and significant correlates include older age, no education, living in a nursing home, and depression. Enhancing lifetime education to improve individuals' cognitive reserves by providing intellectually challenging activities, encouraging living at home rather than in a nursing home, and preventing and treating depression in its early phase could reduce the prevalence of dementia in this population.

Lower CSF amyloid beta peptides and higher F2-isoprostanes in cognitively intact elderly individuals with major depressive disorder

OBJECTIVE

Major depressive disorder is common in the elderly, and symptoms are often not responsive to conventional antidepressant treatment, especially in the long term. Soluble oligomeric and aggregated forms of amyloid beta peptides, especially amyloid beta 42, impair neuronal and synaptic function. Amyloid beta 42 is the main component of plaques and is implicated in Alzheimer's disease. Amyloid beta peptides also induce a depressive state in rodents and disrupt major neurotransmitter systems linked to depression. The authors assessed whether major depression was associated with CSF levels of amyloid beta, tau protein, and F2-isoprostanes in elderly individuals with major depressive disorder and age-matched nondepressed comparison subjects.

METHOD

CSF was obtained from 47 cognitively intact volunteers (major depression group, N=28; comparison group, N=19) and analyzed for levels of soluble amyloid beta, total and phosphorylated tau proteins, and isoprostanes.

RESULTS

Amyloid beta 42 levels were significantly lower in the major depression group relative to the comparison group, and amyloid beta 40 levels were lower but only approaching statistical significance. In contrast, isoprostane levels were higher in the major depression group. No differences were observed in total and phosphorylated tau proteins across conditions. Antidepressant use was not associated with differences in amyloid beta 42 levels.

CONCLUSIONS

Reduction in CSF levels of amyloid beta 42 may be related to increased brain amyloid beta plaques or decreased soluble amyloid beta production in elderly individuals with major depression relative to nondepressed comparison subjects. These results may have implications for our understanding of the pathophysiology of major depression and for the development of treatment strategies.

Plasma beta amyloid level and depression in older adults

BACKGROUND

Older adults with depression have an increased risk of developing dementia. Low plasma beta-amyloid 42 (Aβ42) and Aβ42/Aβ40 have emerged as promising biomarkers of dementia. The association between depression and plasma Aβ is unclear.

METHODS

In this longitudinal study of 988 community-dwelling elders from the Health Aging and Body Composition study, depression was assessed with the Center for Epidemiologic Studies-Depression Scale 10-item version. We determined the association between Aβ42 and Aβ42/Aβ40 tertile and depression at baseline and over 9 years. We also stratified the models to determine if apolipoprotein E e4 allele status modified the associations.

RESULTS

Mean baseline age was 74.0 ± 3.0 years, 51 (5.2%) participants had depression, 545 (55.2%) were women, 531 (53.7%) were black, and 286 (30.7%) had one or more apolipoprotein E e4 allele. At baseline, there was no association between Aβ42/Aβ40 or Aβ42 and depression. Over 9 years, 220 (23.5%) participants developed depression. In adjusted Cox proportional hazards models, among those with one or more e4 allele, low Aβ42/Aβ40 was associated with an increased risk of developing depression over time (low 10.8% vs high 3.2%, hazard ratio = 2.38, 95% confidence interval: 1.15-4.92). Among those with no e4 allele, there was no association between Aβ42/Aβ40 and risk of depression over time (13.3% vs 17.5%, hazard ratio = 0.80, 95% confidence interval: 0.52-1.23; p value for interaction = .003).

CONCLUSIONS

The association between low plasma Aβ42/Aβ40 and increased risk of incident depression among those with one or more apolipoprotein E e4 allele implies a synergistic relationship similar to that found with dementia. Future work should investigate the interrelationships among plasma Aβ42/Aβ40, depression, and dementia.

The association between mental health and cognitive screening scores in older veterans

OBJECTIVES

: To examine overall cognitive screening results and the relationship between cognitive screen score and sociodemographic characteristics, reason for referral, and clinical outcomes of older veterans referred by primary care for a behavioral health assessment.

DESIGN

: Cross-sectional, naturalistic study.

SETTING

: Primary care clinics affiliated with two VA Medical Centers.

PARTICIPANTS

: The sample included 4,325 older veterans referred to the Behavioral Health Laboratory who completed an initial mental health/substance abuse assessment. Veterans were categorized into the following three groups on the basis of cognitive status: within normal limits, possible cognitive impairment, and possible dementia.

MEASUREMENTS

: Sociodemographic and clinical data on reason for referral, cognitive functioning (i.e., Blessed Orientation-Memory-Concentration test), and behavioral health assessment outcomes were extracted from patients' medical records. Data were analyzed using multiple linear and logistic regressions.

RESULTS

: Results of cognitive screenings indicated that the majority of the sample was within normal limits (62.5%), with 25.8%, 8.1%, and 3.6% of patients evidencing possible cognitive impairment, possible dementia, and Blessed Orientation-Memory-Concentration scores of 17 or more, respectively. With regard to reason for referral, patients with greater cognitive impairment were more likely to be identified by the antidepressant case finder than patients with less impairment. Increased age, non-white ethnicity, self-perceived inadequate finances, major depressive disorder, and symptoms of psychosis were associated with greater cognitive impairment.

CONCLUSIONS

: Findings highlight the importance of evaluating cognitive status in older adults who are referred for a behavioral health assessment and/or receive a new mental health/substance abuse diagnosis. Doing so has the potential to improve recognition and treatment of cognitive impairment and dementia, thereby improving quality of care for many older adults.

Mild worry symptoms predict decline in learning and memory in healthy older adults: a 2-year prospective cohort study

OBJECTIVE

: Theoretical models of cognitive aging are increasingly recognizing the importance of anxiety and depressive symptoms in predicting age-related cognitive changes and early dementia. This study examined the association between mild worry and depressive symptoms, and cognitive function in healthy, community-dwelling older adults.

METHOD

: A total of 263 healthy older adults participated in an observational prospective cohort study that assessed worry and depression symptoms, and a broad range of cognitive functions over a 2-year period.

RESULTS

: Older adults with mildly elevated worry symptoms at baseline performed worse than older adults with minimal worry symptoms on measures of visual and paired associate learning. They were also more likely to show clinically significant (> 1.5 standard deviation) decline in visual learning and memory at a 2-year follow-up assessment (9.4% versus 2.5%; odds ratio = 3.8).

CONCLUSION

: Assessment of worry symptoms, even mild levels, may have utility in predicting early cognitive decline in healthy, community-dwelling older adults.

Depressive symptoms predict decline in perceptual speed in older adulthood

Depressive symptoms and cognitive decline are associated in older age, but research is inconsistent about whether one condition influences the development of the other. We examined the directionality of relations between depressive symptoms and perceptual speed using bivariate dual change score models. Assessments of depressive symptoms and perceptual speed were completed by 1,206 nondemented older adults at baseline, and after 2, 8, 11, and 15 years. After controlling for age, education, baseline general cognitive ability, and self-reported health, allowing depressive symptoms to predict subsequent change in perceptual speed provided the best fit. More depressive symptoms predicted subsequently stronger declines in perceptual speed over time lags of 1 year.

Depression, hippocampal volume changes, and cognitive decline in a clinical sample of older depressed outpatients and non-depressed controls

OBJECTIVE

The aim of this study was to develop and test a model of depression, hippocampal changes, and cognitive decline.

METHOD

Participants were 248 community-dwelling, depressed patients and 147 healthy, non-depressed individuals 60 years and older. Participants received a structured interview assessing current depressive symptoms and past depressive episodes, completed cognitive testing with the Mini Mental State Examination (MMSE), and underwent structural Magnetic Resonance Imaging (MRI) of the brain. For up to 10 years, assessment of depressive symptoms and MMSE administration was repeated at least annually, and MRI was repeated every two years.

RESULTS

Regression analyses demonstrated that depression diagnosis at baseline predicted decrease in right (but not left) hippocampal volume over a four-year period. Analyses using structural equation modeling demonstrated that a decrease in left and right hippocampal volumes predicted decrease in MMSE score over four years.

CONCLUSION

Results provide some evidence for relationships between depression and decrease in right hippocampal volume, and between hippocampal volume and MMSE score. This would be consistent with depression as a causal factor in subsequent cognitive decline. Plausible biological mechanisms include a glucocorticoid cascade or a facilitating effect of depression on amyloid-beta plaque formation. Future studies should examine the relationship between hippocampal volume and specialized memory measures, as well as between depression diagnosis and volume of other brain structures.

At-fault motor vehicle crash risk in elderly patients treated with antidepressants

OBJECTIVE

To assess whether antidepressant treatment is associated with a temporary increase in the risk of a motor vehicle crash among older adults.

DESIGN

Population-based case-only time-to-event analysis.

SETTING AND SUBJECTS

Data from transportation and healthcare databases for adults age 65 and older in Ontario, Canada, between January 1, 2000, and October 31, 2007. Consecutive adults who had a motor vehicle crash anytime following their 66th birthday.

MEASUREMENTS

The primary exposure variable was treatment with antidepressant medication, and the primary outcome measure was a motor vehicle crash.

RESULTS

A total of 159,678 individuals had a crash during the study, of whom 7,393 (5%) received an antidepressant in the month prior to the crash. The hazard ratio (HR) of crash associated with second-generation antidepressants was 1.10 (95% confidence interval [CI]: 1.07-1.13, χ² = 41.77, df = 1, p <0.0001), adjusted for gender, license suspensions, and other medications, but the risk for first-generation antidepressants was not significant. The increased risk was restricted to those who were also concurrently prescribed a benzodiazepine (adjusted HR: 1.23, 95% CI: 1.17-1.28, χ² = 85.28, df = 1, p <0.0001) or a strong anticholinergic medication (adjusted HR: 1.63, 95% CI: 1.57-1.69, χ² = 627.31, df = 1, p <0.0001), and was confined to crashes where the patient was at fault. The increased risk was apparent for the first 3-4 months following initiation of an antidepressant and returned to baseline thereafter.

CONCLUSIONS

Prescriptions for second-generation antidepressants in older adults are associated with a modest increased risk of motor vehicle crashes, when combined with other medications that can impair cognition.

Does late onset depression predispose to dementia? A retrospective, case-controlled study

BACKGROUND

Recent research suggests that there are clinical and biologic characteristics typical of late onset depression (LOD). Furthermore, evidence has been put forward that LOD may be a prodrome of dementia.

OBJECTIVE

This study aims to assess the association between LOD and the development of dementia.

SETTING

The study was conducted in a tertiary care, university-affiliated mental health center providing services for an urban catchment population of 800,000 subjects.

METHOD

A retrospective, case-controlled study was used.

RESULTS

Fifty-one patients with LOD who developed dementia at least 1 year after diagnosis of LOD were defined as the index group: 18 males and 33 females, with a mean age of 75.4 ± 9.2 years. These were compared with 51 patients with LOD who did not develop dementia during a 10-year follow-up period. Dementia types were as follows: 73% Alzheimer disease, 24% vascular and mixed dementia, and 3% Parkinson dementia. Patients with LOD who developed dementia were significantly characterized by having longer hospitalization for their first depressive episode (P = .048), having a family history of dementia (P = .022), and having been exposed to the Holocaust as young adults (P = .013).

CONCLUSIONS

Patients with a history of significant traumatic experience in early life and a prolonged onset of depression may be at particular risk of developing dementia. This issue requires further long-term prospective studies.

Subtypes of mild cognitive impairment among the elderly with major depressive disorder in remission

BACKGROUND

Cognitive impairment in remitted late-life depression varies and might be associated with greater risk of dementia in some individuals. This study aimed to classify the subtypes of mild cognitive impairment (MCI) in late-life major depressive disorder in remission and to examine their clinical correlates and structural magnetic resonance imaging (MRI) features.

METHODS

Elderly patients with major depressive disorder in remission and elderly comparisons were examined by a comprehensive battery of cognitive tasks. Proposed diagnostic criteria were used for MCI classification, and the degree of brain atrophy and white matter hyperintensity on MRI were evaluated.

RESULTS

We found information-processing speed and memory were independent cognitive domains associated with late-life remitted major depressive disorder. Of the study cohort, 52.3% met the definition of MCI, including 28.5% with amnestic MCI (aMCI) and 23.8% with nonamnestic MCI (naMCI). A clinical correlate of aMCI was the late-onset of disorder (OR = 4.76; 95% CI = 1.57, 14.40) and of naMCI was a higher score on the Framingham stroke risk scale (OR = 1.39; 95% CI = 1.12, 1.72). The odds ratio of highest quartile of ventricular atrophy for aMCI compared to the comparisons was 3.65 (95% CI = 1.22, 10.96).

CONCLUSIONS

The central cognitive impairments among the elderly with major depressive disorder in remission were memory and information-processing speed, and over half of the subjects met the MCI diagnostic criteria. Different risk factors existed for the subtypes of aMCI and naMCI. Later-age onset of first episode and ventricular atrophy were associated with aMCI, whereas vascular risk factor were associated with naMCI. We suggest there were different pathogeneses between aMCI and naMCI in late-life major depressive disorder.

Prevalence and predictors of anticholinergic agents in elderly outpatients with dementia

BACKGROUND

Anticholinergic medications, although frequently used in elderly populations, are associated with cognitive impairment and constitute significant concern for patients with dementia.

OBJECTIVE

The purpose of our study was to examine patterns and predictors of prescribing anticholinergic agents for elderly outpatients with dementia.

METHODS

We combined data from the 2006-2007 National Ambulatory Medical Care Survey and the outpatient department component of National Hospital Ambulatory Medical Care Survey to analyze patient visits by elderly persons (aged ≥65 years) with dementia. Anticholinergic drugs were identified using the Anticholinergic Drug Scale, which classifies anticholinergic drugs into four levels (0-3) in increasing order of anticholinergic activity. Descriptive analysis using sampling weights was used to evaluate patterns of anticholinergic drug prescription, especially prescribing of medications with clinically significant anticholinergic activity (ie, levels 2 or 3). Multiple logistic regression was used in the conceptual framework of the Andersen Behavioral Model to examine the predisposing, enabling, and need factors associated with prescribing of medications with clinically significant anticholinergic activity.

RESULTS

According to the national surveys there were a total of 6.8 million (95% CI, 5.27-8.44 million; 0.32%) ambulatory care visits for dementia. Approximately 43% (42.86%; 95% CI, 35.24-50.48) of these visits involved prescribing at least one anticholinergic drug; and 10.07% of visits involved prescribing levels 2 or 3 anticholinergic medications. The predisposing factor, age (75-84 years; odds ratio [OR] = 0.25; 95% CI, 0.07-0.87), and the need factors, acetylcholinesterase inhibitor use (OR = 0.25; 95% CI, 0.07-0.86) and comorbid mood disorders (OR = 0.12; 95% CI, 0.02-0.73), were associated with decreased likelihood of prescribing medications with clinically significant anticholinergic activity. The need factor total number of medications prescribed (OR = 1.45, 95% CI, 1.20-1.75) increased the likelihood of these prescriptions being administered.

CONCLUSIONS

One in 10 outpatient visits by elderly persons with dementia involved prescribing medications with clinically significant anticholinergic activity. Given their adverse cognitive effects, there is a strong need to optimize anticholinergic drug prescribing in vulnerable elderly outpatients with dementia.

Incident dementia in a defined older Chinese population

Background

Current knowledge about incident dementia is mainly derived from studies undertaken in the West, showing that dementia is related to older age, low socio-economic status, lack of social network, depression and cardiovascular disease risk factors. We know little about incidence and predictors of dementia in China, where the prevalence is increasing and the patterns of risk factors are different.

Methods

Using a standard interview method, we examined 1526 non-demented people aged ≥65 years who had at least minimal educational level in China in a 7.5-year follow up. Incident dementia was diagnosed by GMS-AGECAT algorithms and psychiatrists.

Results

Age-standardised incidence of dementia was 14.7 per 1000 person-years (95%CI 11.3–18.2 per 1000 person-years). The increased risk was significantly associated with age, female gender (adjusted odds ratio 2.48, 95%CI 1.20–5.13), low educational levels, smoking, angina (2.58, 1.01–6.59) and living with fewer family members. Among participants with low educational level, the increased risk was associated with higher income, and with the highest and lowest occupational classes; adjusted odds ratio 2.74 (95%CI 1.12–6.70) for officers/teachers, 3.11 (1.61–6.01) for manual labourers/peasants.

Conclusions

Our findings of high incidence of dementia and increased risk among people having low education levels but high income suggest a more potential epidemic and burden of dementia populations in China. Maintaining social network and activities and reducing cardiovascular factors in late life could be integrated into current multi-faceted preventive strategies for curbing the epidemic of dementia.

Striatal Hypodensities, Not White Matter Hypodensities on CT, Are Associated with Late-Onset Depression in Alzheimer's Disease

This study examined whether there were neuroanatomical differences evident on CT scans of individuals with dementia who differed on depression history. Neuroanatomical variables consisted of visual ratings of frontal lobe deep white matter, subcortical white matter, and subcortical gray matter hypodensities in the CT scans of 182 individuals from the Study of Dementia in Swedish Twins who were diagnosed with dementia and had information on depression history. Compared to individuals with Alzheimer's disease and no depression, individuals with Alzheimer's disease and late-onset depression (first depressive episode at age 60 or over) had a greater number of striatal hypodensities (gray matter hypodensities in the caudate nucleus and lentiform nucleus). There were no significant differences in frontal lobe deep white matter or subcortical white matter. These findings suggest that late-onset depression may be a process that is distinct from the neurodegenerative changes caused by Alzheimer's disease.

Early parental death and remarriage of widowed parents as risk factors for Alzheimer disease: the Cache County study

OBJECTIVES

Early parental death is associated with lifelong tendencies toward depression and chronic stress. We tested the hypothesis that early parental death is associated with higher risk for Alzheimer disease (AD) in offspring.

DESIGN

A population-based epidemiological study of dementia with detailed clinical evaluations, linked to one of the world's richest sources of objective genealogical and vital statistics data.

SETTING

Home visits with residents of a rural county in northern Utah.

PARTICIPANTS

4,108 subjects, aged 65-105.

MEASUREMENTS

Multistage dementia ascertainment protocol implemented in four triennial waves, yielding expert consensus diagnoses of 570 participants with AD and 3,538 without dementia. Parental death dates, socioeconomic status, and parental remarriage after widowhood were obtained from the Utah Population Database, a large genealogical database linked to statewide birth and death records.

RESULTS

Mother's death during subject's adolescence was significantly associated with higher rate of AD in regression models that included age, gender, education, APOE genotype, and socioeconomic status. Father's death before subject age 5 showed a weaker association. In stratified analyses, associations were significant only when the widowed parent did not remarry. Parental death associations were not moderated by gender or APOE genotype. Findings were specific to AD and not found for non-AD dementia.

CONCLUSIONS

Parental death during childhood is associated with higher prevalence of AD, with different critical periods for father's versus mother's death, with strength of these associations attenuated by remarriage of the widowed parent.

The correlation of plasma Aβ42 levels, depressive symptoms, and cognitive function in the Korean elderly

OBJECTIVES

This study aims to investigate whether plasma amyloid beta 1-42 (Aβ42) levels are associated with depressive symptoms and/or cognitive function in community dwelling elderly.

METHODS

Subjects were 123 participants of a population-based project designed to screen community dwelling elderly older than 65 years old in Gangwon Province, Korea, for the early detection of depression and dementia. Symptoms of depression were assessed using the SGDS-K (Short Geriatric Depression Scale-Korean version), and the MMSE-KC (Mini-Mental State Examination-Korean version) was used to assess cognitive function. Plasma Aβ42 levels were measured with the human amyloid beta ELISA Kit.

RESULTS

The elderly with depressive symptoms (SGDS-K score ≥ 8) had higher plasma Aβ42 levels than those without depressive symptoms (SGDS-K score<8) (p<0.1). Plasma Aβ42 levels were positively correlated with SGDS-K scores (p<0.05). However, MMSE-KC scores were inversely associated with plasma Aβ42 levels (p<0.01). Plasma β42 levels were also associated with MMSE-KC (F=8.07, p<0.01) and SGDS-K (F=4.53, p<0.05) by generalized linear model (GLM) with controlling age, sex and education.

CONCLUSION

Plasma Aβ42 levels were associated with depressive symptoms and cognitive function in community dwelling elderly. The present study supports the possibility that plasma Aβ may be involved in the development of late onset depression.

Biomarkers for major depression and its delineation from neurodegenerative disorders

Major depressive disorders (MDD) are among the most debilitating diseases worldwide and occur with a high prevalence in elderly individuals. Neurodegenerative diseases (in particular Alzheimer's disease, AD) do also show a strong age-dependent increase in incidence and prevalence among the elderly population. A high number of geriatric patients with MDD show cognitive deficits and a very high proportion of AD patients present co-morbid MDD, which poses difficult diagnostic and prognostic questions. Especially in prodromal and in very early stages of AD, it is almost impossible to differentiate between pure MDD and MDD with underlying AD. Here, we give a comprehensive review of the literature on the current state of candidate biomarkers for MDD ("positive MDD markers") and briefly refer to established and validated diagnostic AD biomarkers in order to rule out underlying AD pathophysiology in elderly MDD subjects with cognitive impairments ("negative MDD biomarkers"). In summary, to date there is no evidence for positive diagnostic MDD biomarkers and the only way to delineate MDD from AD is to use "negative MDD" biomarkers. Because of this highly unsatisfactory current state of MDD biomarker research, we propose a research strategy targeting to detect and validate positive MDD biomarkers, which is based on a complex (genetic, molecular and neurophysiological) biological model that incorporates current state of the art knowledge on the pathobiology of MDD. This model delineates common pathways and the intersection between AD and MDD. Applying these concepts to MDD gives hope that positive MDD biomarkers can be successfully identified in the near future.

Incidence and predictive factors of depressive symptoms in Alzheimer's disease: the REAL.FR study

BACKGROUND

Many patients develop psychiatric and behavioral disturbances in the course of Alzheimer's disease (AD). Among these disturbances, depressive symptoms are frequent and affect nearly 40% of patients. The natural history and course of such symptoms in AD, and in particular the predictive factors, are little known. We studied the incidence and risk factors for the development of the first depressive symptoms in AD.

DESIGN

Multicenter prospective study.

PARTICIPANTS

Three hundred twelve AD patients from the French Network on AD (REAL.FR) without depression and without antidepressant treatment at baseline were followed up and assessed every 6 months for 4 years. During follow-up, all events occurring between two visits were carefully recorded.

MEASUREMENTS

We used the Neuropsychiatric Inventory (NPI) for comprehensive evaluation of behavioral and psychological symptoms and depressive symptoms in particular. A multivariate analysis was performed using a backward stepwise Cox proportional hazards model.

RESULTS

The incidence of depressive symptoms was 17.45% person/years, 95%CI (13.88-21.02). Among non-time dependent variables, duration of disease (RR=0.51; 95%CI: 0.30-0.85, p=0.0102) and the number of comorbid conditions (RR=0.45; 95%CI: 0.24-0.83, p=0.0115) were protective factors against the development of depressive symptoms. Agitation/aggression (RR=1.96; 95%CI: 1.19-3.23, p=0.0078) and sleep disturbances (RR=2.65; 95%CI: 1.40-5.00, p=0.0026) were time-dependent variables predictive of depressive symptoms.

CONCLUSION

Better knowledge of predictive factors of mood disturbances in AD will enable clinicians to set up appropriate management of their patients. As published longitudinal studies are few, further works should be carried out to improve knowledge of the pattern and course of depression and depressive symptoms in AD.

The projected effect of risk factor reduction on Alzheimer's disease prevalence

At present, about 33·9 million people worldwide have Alzheimer's disease (AD), and prevalence is expected to triple over the next 40 years. The aim of this Review was to summarise the evidence regarding seven potentially modifiable risk factors for AD: diabetes, midlife hypertension, midlife obesity, smoking, depression, cognitive inactivity or low educational attainment, and physical inactivity. Additionally, we projected the effect of risk factor reduction on AD prevalence by calculating population attributable risks (the percent of cases attributable to a given factor) and the number of AD cases that might be prevented by risk factor reductions of 10% and 25% worldwide and in the USA. Together, up to half of AD cases worldwide (17·2 million) and in the USA (2·9 million) are potentially attributable to these factors. A 10-25% reduction in all seven risk factors could potentially prevent as many as 1·1-3·0 million AD cases worldwide and 184,000-492,000 cases in the USA.

The complex relationship between depression and dementia

Dementia and depression are mental health problems that are commonly encountered in neuropsychiatric practice in the elderly. Approximately, half of the patients with late-onset depression have cognitive impairment. The prevalence of depression in dementias has been reported to be between 9 and 68%. Depression has been both proposed to be a risk factor for dementia as well as a prodrome of dementia. This article is a selective literature review of the complex relationship between the two conditions covering definitions, epidemiology, related concepts, treatment, and emerging biomarkers. The methodological issues and the mechanisms underlying the relationship are also highlighted. The relationship between the two disorders is far from conclusive.

Memory predicts changes in depressive symptoms in older adults: a bidirectional longitudinal analysis

OBJECTIVES

Although research indicates that depressive symptoms and memory performance are related in older adults, the temporal associations between these variables remain unclear. This study examined whether depressive symptoms predicted later memory change and whether memory predicted later change in depressive symptoms.

METHODS

The sample consisted of more than 14,000 adults from the Health and Retirement Study, a biannual longitudinal study of health and retirement in Americans older than age 50 years. Measures of delayed recall and depressive symptoms served as the main study variables. We included age, sex, education, and history of vascular diseases as covariates.

RESULTS

Using dynamic change models with latent difference scores, we found that memory performance predicted change in depressive symptoms 2 years later. Depressive symptoms did not predict later change in memory. The inclusion of vascular health variables diminished the size of the observed relationship, suggesting that biological processes may partially explain the effect of memory on depressive symptoms.

IMPLICATIONS

Future research should explore both biological and psychological processes that may explain the association between worse memory performance and subsequent increases in depressive symptoms.

Depression and risk of developing dementia

Depression is highly common throughout the life course and dementia is common in late life. Depression has been linked with dementia, and growing evidence implies that the timing of depression may be important in defining the nature of this association. In particular, earlier-life depression (or depressive symptoms) has consistently been associated with a more than twofold increase in dementia risk. By contrast, studies of late-life depression and dementia risk have been conflicting; most support an association, yet the nature of this association (for example, if depression is a prodrome or consequence of, or risk factor for dementia) remains unclear. The likely biological mechanisms linking depression to dementia include vascular disease, alterations in glucocorticoid steroid levels and hippocampal atrophy, increased deposition of amyloid-β plaques, inflammatory changes, and deficits of nerve growth factors. Treatment strategies for depression could interfere with these pathways and alter the risk of dementia. Given the projected increase in dementia incidence in the coming decades, understanding whether treatment for depression alone, or combined with other regimens, improves cognition is of critical importance. In this Review, we summarize and analyze current evidence linking late-life and earlier-life depression and dementia, and discuss the primary underlying mechanisms and implications for treatment.

Latest Advances on Interventions that May Prevent, Delay or Ameliorate Dementia

OBJECTIVES

IN THIS PAPER WE AIM TO: (1) identify and review midlife risk factors that may contribute to the development of dementia and that may be amenable to intervention; (2) review advances made in our understanding of the most common cause of dementia, Alzheimer's disease (AD), where current pharmacological studies have aimed to modify the disease course; and (3) explore other interventions that may slow cognitive decline in those with AD.

METHODS

A review of the literature was conducted to look for interventions that may modify the risk of incident dementia or that may modify symptom progression in those with diagnosed dementia.

RESULTS

(1) Midlife risks identified as amenable to intervention include blood pressure, diabetes, elevated cholesterol, poor psychosocial and lifestyle factors. (2) The leading drugs in development can be grouped by their principal target: anti-amyloid, anti-tau and mitochondrial stability. However to date, there have been no successes in late stage Phase III trials of putative disease-modifying drugs for AD. (3) Once the diagnosis of dementia has been made there is little that can slow the rate of decline. Possible exceptions include the use of exercise and antihypertensive medication with some nootropic medication showing promise in small trials.

CONCLUSION

(1) It is clear that there are several risk factors in midlife that may lead to a greater likelihood of developing dementia. However, there is no simple intervention to modify these risks. It seems sensible to conclude from the data that avoiding high blood pressure, controlling cholesterol and diabetes as well as maintaining a healthy diet and lifestyle may lower the risk of developing dementia. (2) The need for better outcome measures in clinical trials is evident and may, in part, explain the numerous failures in late-stage clinical trials of disease-modifying drugs. Improved diagnostic test batteries to reduce population heterogeneity in early intervention studies will be required for robust clinical trials in the future. (3) Current research indicates that there is little that can delay decline; however, future trials may wish to focus on nootropics.

Cognitive function and risk for depression in old age: a meta-analysis of published literature

BACKGROUND

We assessed the relationship between cognitive impairment (including mild cognitive impairment with no signs of dementia, and dementia) and risk for depression in old age (60 years and older).

METHODS

MEDLINE, EMBASE and the Cochrane Library database were used to identify potential studies. All of the clinical studies that produced data on the association between cognitive function and risk of depression among individuals aged 55 years or older were identified and included in this review. The studies were classified into cross-sectional and longitudinal subsets. The quantitative meta-analysis of cross-sectional and longitudinal studies were performed. For prevalence and incidence rates of depression, odds risk (OR) and relative risk (RR) were calculated, respectively.

RESULTS

Since all but two studies found in the search were for individuals aged 60 years or over, we assessed and reported on results for this larger group only. In this review we included 13 cross-sectional and four prospective longitudinal studies. The quantitative meta-analysis showed that, in old age, individuals with non-dementia cognitive impairment had neither significant higher prevalence nor incidence rates of depression than those without (odds risk (OR): 1.48, 95% confidence intervals (95% CI): 0.87-2.52; relative risk (RR): 1.12, 95% CI: 0.62-2.01). In old age, individuals with dementia had both significant higher prevalence and incidence rates of depression than those without (OR: 1.82, 95% CI: 1.15-2.89; RR: 3.92, 95% CI: 1.93-7.99).

CONCLUSIONS

Despite the methodological limitations of this meta-analysis, we found that in old age, there was no association between depression and cognitive impairment with no dementia; however, there was a definite association between depression and dementia and thus dementia might be a risk for depression.

Epidemiology of Alzheimer disease

The global prevalence of dementia is estimated to be as high as 24 million, and is predicted to double every 20 years through to 2040, leading to a costly burden of disease. Alzheimer disease (AD) is the leading cause of dementia and is characterized by a progressive decline in cognitive function, which typically begins with deterioration in memory. Before death, individuals with this disorder have usually become dependent on caregivers. The neuropathological hallmarks of the AD brain are diffuse and neuritic extracellular amyloid plaques-which are frequently surrounded by dystrophic neurites-and intracellular neurofibrillary tangles. These hallmark pathologies are often accompanied by the presence of reactive microgliosis and the loss of neurons, white matter and synapses. The etiological mechanisms underlying the neuropathological changes in AD remain unclear, but are probably affected by both environmental and genetic factors. Here, we provide an overview of the criteria used in the diagnosis of AD, highlighting how this disease is related to, but distinct from, normal aging. We also summarize current information relating to AD prevalence, incidence and risk factors, and review the biomarkers that may be used for risk assessment and in diagnosis.

The fate of the 0.5s: predictors of 2-year outcome in mild cognitive impairment

Impairments in executive cognition (EC) may be predictive of incident dementia in patients with mild cognitive impairment (MCI). The present study examined whether specific EC tests could predict which MCI individuals progress from a Clinical Dementia Rating (CDR) score of 0.5 to a score ≥1 over a 2-year period. Eighteen clinical and experimental EC measures were administered at baseline to 104 MCI patients (amnestic and non-amnestic, single- and multiple-domain) recruited from clinical and research settings. Demographic characteristics, screening cognitive measures and measures of everyday functioning at baseline were also considered as potential predictors. Over the 2-year period, 18% of the MCI individuals progressed to CDR ≥ 1, 73.1% remained stable (CDR = 0.5), and 4.5% reverted to normal (CDR = 0). Multiple-domain MCI participants had higher rates of progression to dementia than single-domain, but amnestic and non-amnestic MCIs had similar rates of conversion. Only three EC measures were predictive of subsequent cognitive and functional decline at the univariate level, but they failed to independently predict progression to dementia after adjusting for demographic, other cognitive characteristics, and measures of everyday functioning. Decline over 2 years was best predicted by informant ratings of subtle functional impairments and lower baseline scores on memory, category fluency, and constructional praxis.

Depressive symptoms and incidence of mild cognitive impairment and probable dementia in elderly women: the Women's Health Initiative Memory Study

OBJECTIVES

To examine whether significant depressive symptoms in postmenopausal women increases the risk of subsequent mild cognitive impairment (MCI) and dementia.

DESIGN

Prospective cohort study.

SETTING

Thirty nine of the 40 Women's Health Initiative (WHI) clinical centers that participated in a randomized clinical trial of hormone therapy.

PARTICIPANTS

Six thousand three hundred seventy-six postmenopausal women without cognitive impairment aged 65 to 79 at baseline.

MEASUREMENTS

Depressive disorders were assessed using an eight-item Burnam algorithm and followed annually for a mean period of 5.4 years. A central adjudication committee classified the presence of MCI and probable dementia based on an extensive neuropsychiatric examination.

RESULTS

Eight percent of postmenopausal women in this sample reported depressive symptoms above a 0.06 cut point on the Burnam algorithm. Depressive disorder at baseline was associated with greater risk of incident MCI (hazard ratio (HR)=1.98, 95% confidence interval (CI)=1.33-2.94), probable dementia (HR=2.03, 95% CI=1.15-3.60), and MCI or probable dementia (HR=1.92, 95% CI=1.35-2.73) after controlling for sociodemographic characteristics, lifestyle and vascular risk factors, cardiovascular and cerebrovascular disease, antidepressant use, and current and past hormone therapy status. Assignment to hormone therapy and baseline cognitive function did not affect these relationships. Women without depression who endorsed a remote history of depression had a higher risk of developing dementia.

CONCLUSION

Clinically significant depressive symptoms in women aged 65 and older are independently associated with greater incidence of MCI and probable dementia.

The diagnostic challenge of psychiatric symptoms in neurodegenerative disease: rates of and risk factors for prior psychiatric diagnosis in patients with early neurodegenerative disease

OBJECTIVE

To identify rates of and risk factors for psychiatric diagnosis preceding the diagnosis of neurodegenerative disease.

METHOD

Systematic, retrospective, blinded chart review was performed of 252 patients with a neurodegenerative disease diagnosis seen in our specialty clinic between 1999 and 2008. Neurodegenerative disease diagnoses included behavioral-variant frontotemporal dementia (n = 69), semantic dementia (n = 41), and progressive nonfluent aphasia (n = 17) (all meeting Neary research criteria); Alzheimer's disease (n = 65) (National Institute of Neurologic and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association research criteria); corticobasal degeneration (n = 25) (Boxer research criteria); progressive supranuclear palsy (n = 15) (Litvan research criteria); and amyotrophic lateral sclerosis (n = 20) (El Escorial research criteria). Reviewers remained blinded to each patient's final neurodegenerative disease diagnosis while reviewing charts. Extensive caregiver interviews were conducted to ensure accurate and reliable diagnostic histories. For each patient, we recorded history of psychiatric diagnosis, family psychiatric and neurologic history, age at symptom onset, and demographic information.

RESULTS

A total of 28.2% of patients with a neurodegenerative disease received a prior psychiatric diagnosis. Depression was the most common psychiatric diagnosis in all groups. Behavioral-variant frontotemporal dementia patients received a prior psychiatric diagnosis significantly more often (50.7%; P < .001) than patients with Alzheimer's disease (23.1%), semantic dementia (24.4%), or progressive nonfluent aphasia (11.8%) and were more likely to receive diagnoses of bipolar disorder or schizophrenia than were patients with other neurodegenerative diseases (P < .001). Younger age (P < .001), higher education (P < .05), and a family history of psychiatric illness (P < .05) increased the rate of prior psychiatric diagnosis in patients with behavioral-variant frontotemporal dementia. Cognitive, behavioral, and emotional characteristics did not distinguish patients who did or did not receive a prior psychiatric diagnosis.

CONCLUSIONS

Neurodegenerative disease is often misclassified as psychiatric disease, with behavioral-variant frontotemporal dementia patients at highest risk. While this study cannot rule out the possibility that psychiatric disease is an independent risk factor for neurodegenerative disease, when patients with neurodegenerative disease are initially classified with psychiatric disease, the patient may receive delayed, inappropriate treatment and be subject to increased distress. Physicians should consider referring mid- to late-life patients with new-onset neuropsychiatric symptoms for neurodegenerative disease evaluation.

Intact cognition in depressed elderly veterans providing adequate effort

Geriatric depression has been associated with cognitive impairments, but whether suboptimal effort contributes to these deficits is unknown. This study investigated differences in cognitive functioning between depressed and nondepressed elderly veterans, before and after excluding patients who provided suboptimal effort on testing at a memory disorders clinic. Patients diagnosed with a depressive disorder performed more poorly than nondepressed patients on almost all Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) indices, but these differences became nonstatistically significant after excluding patients who provided suboptimal effort. However, when patients were classified as normal, mildly, or severely depressed based on Geriatric Depression Scale scores, these groups were not significantly different on RBANS indices, regardless of whether patients who provided suboptimal effort were included or excluded from analyses. The findings suggest that cognitive deficits in depression reported in previous research may be attributable to suboptimal effort and that identifying depression via clinical diagnosis or psychometric data may affect this trend.

Dementia in Swedish twins: predicting incident cases

Thirty same-sex twin pairs were identified in which both members were assessed at baseline and one twin subsequently developed dementia, at least 3 years subsequent to the baseline measurement, while the partner remained cognitively intact for at least three additional years. Eighteen of the 30 cases were diagnosed with Alzheimer's disease. Baseline assessments, conducted when twins' average age was 70.6 (SD = 6.8), included a mailed questionnaire and in-person testing. Which twin would develop dementia was predicted by less favorable lipid values (higher apoB, ratio of apoB to apoA1, and total cholesterol), poorer grip strength, and-to a lesser extent-higher emotionality on the EAS Temperament Scale. Given the long preclinical period that characterizes Alzheimer's disease, these findings may suggest late life risk factors for dementia, or may reflect changes that are part of preclinical disease.

Plasma amyloid beta-42 independently predicts both late-onset depression and Alzheimer disease

OBJECTIVES

Depression in the elderly might represent a prodromal phase of Alzheimer disease (AD). High levels of plasma amyloid beta-42 (Aβ42) were found in prestages of AD and also in depressed patients in cross-sectional studies. This study examined the association of emerging late-onset depression (LOD) and AD with plasma Aβ42 in a sample of never depressed and not demented persons at baseline.

DESIGN

Prospective 5-year longitudinal study.

PARTICIPANTS

A community dwelling of older adults (N = 331) from the Vienna Transdanube Aging study.

MEASUREMENTS

Laboratory measurements, cognitive functioning, and depressive symptoms were assessed at baseline, 2.5, and 5 years follow-ups.

RESULTS

After exclusion of converters to AD, regression analysis revealed that higher plasma Aβ42 at baseline was a positive predictor for conversion to first episode of LOD. Independent of whether persons with mild cognitive impairment (MCI) at 2.5 years were included or excluded into regressions, higher plasma Aβ42 at baseline was a significant predictor for the development of probable or possible AD at 5 years. Higher conversion to AD was also associated with male gender but not with either higher scores on the Geriatric Depression Scale (GDS), with stroke or cerebral infarction nor apolipoprotein E ε4 allele. No association was found for an interaction between plasma Aβ42 levels and GDS.

CONCLUSIONS

Higher plasma Aβ42 at baseline predicted the development of first episode of LOD and conversion to probable or possible AD. Emerging depression as measured by scores on GDS at the 2.5-year follow-up, either alone or as an interaction factor with plasma Aβ42, failed to predict the conversion to AD at 5 years.

Specific psychological and behavioral symptoms of depression in patients with dementia

Behavioral and psychological symptoms in dementia (BPSD) are very common, with 90% of patients experiencing at least one during the course of the disease. One-third of persons with dementia have depressive symptoms, and concomitant BPSD are very likely.

OBJECTIVE

This study aimed to characterize the psychological and behavioral manifestations of depression in patients with dementia.

METHODS

We recruited patients with dementia from several nursing homes in the Limousin region of France. Depression was as diagnosed by the Cornell Scale for Depression in Dementia (CSDD) with a cut-off of 7, and BPSD were assessed using the Neuropsychiatric Inventory (NPI).

RESULTS

Of 319 patients with dementia, 42.9% (n =137) were depressed and 75.9% (n = 242) had BPSD. All BPSD were significantly (p < 0.0001) more prevalent among depressed patients, but no significant differences were observed according to sex and age. The NPI showed that the most common additional symptoms in depressed patients were agitation (43.2%), anxiety (42.3%) and irritability (40.1%). Four NPI-based factors were indentified (63.9% of the common variance): factor 1 (disinhibition, irritability, agitation, anxiety), factor 2 (sleep disturbance, aberrant motor behavior, apathy), factor 3 (elation, hallucination, delirium) and the last with eating disorders. Depression in dementia patients was significantly associated with disinhibition, irritability, agitation, and anxiety.

CONCLUSION

BPSD are common and a major problem. Before addressing them as isolated symptoms, it is important to consider comorbidity with depression in order to optimize the therapeutic approach.

Distinct functional networks associated with improvement of affective symptoms and cognitive function during citalopram treatment in geriatric depression

Variability in the affective and cognitive symptom response to antidepressant treatment has been observed in geriatric depression. The underlying neural circuitry is poorly understood. This study evaluated the cerebral glucose metabolic effects of citalopram treatment and applied multivariate, functional connectivity analyses to identify brain networks associated with improvements in affective symptoms and cognitive function. Sixteen geriatric depressed patients underwent resting positron emission tomography (PET) studies of cerebral glucose metabolism and assessment of affective symptoms and cognitive function before and after 8 weeks of selective serotonin reuptake inhibitor treatment (citalopram). Voxel-wise analyses of the normalized glucose metabolic data showed decreased cerebral metabolism during citalopram treatment in the anterior cingulate gyrus, middle temporal gyrus, precuneus, amygdala, and parahippocampal gyrus. Increased metabolism was observed in the putamen, occipital cortex, and cerebellum. Functional connectivity analyses revealed two networks which were uniquely associated with improvement of affective symptoms and cognitive function during treatment. A subcortical-limbic-frontal network was associated with improvement in affect (depression and anxiety), while a medial temporal-parietal-frontal network was associated with improvement in cognition (immediate verbal learning/memory and verbal fluency). The regions that comprise the cognitive network overlap with the regions that are affected in Alzheimer's dementia. Thus, alterations in specific brain networks associated with improvement of affective symptoms and cognitive function are observed during citalopram treatment in geriatric depression.

Designing prevention programmes to reduce incidence of dementia: prospective cohort study of modifiable risk factors

OBJECTIVE

To estimate the percentage reduction in incidence of dementia that would be obtained if specific risk factors were eliminated.

DESIGN

Prospective seven year cohort study.

SETTING

General population, Montpellier, France.

PARTICIPANTS

1433 people aged over 65 with a mean baseline age of 72.5 (SD 5.1) years.

MAIN OUTCOME MEASURES

Diagnosis of mild cognitive impairment or dementia established by a standardised neurological examination.

RESULTS

Cox models were constructed to derive hazard ratios and determine confounding and interaction effects for potentially modifiable risk factors for dementia. Mean percentage population attributable fractions were calculated with 95% confidence intervals derived from bootstrapping for seven year incidence of mild cognitive impairment or dementia. The final model retained crystallised intelligence (population attributable fraction 18.11%, 95% confidence interval 10.91% to 25.42%), depression (10.31%, 3.66% to 17.17%), fruit and vegetable consumption (6.46%, 0.15% to 13.06%), diabetes (4.88%, 1.87% to 7.98%), and apolipoprotein E epsilon4 allele (7.11%, 2.44% to 11.98%).

CONCLUSIONS

Increasing crystallised intelligence and fruit and vegetable consumption and eliminating depression and diabetes are likely to have the biggest impact on reducing the incidence of dementia, outweighing even the effect of removing the principal known genetic risk factor. Although causal relations cannot be concluded with certainty, the study suggests priorities that may inform public health programmes.

Recurrent depressive symptoms and the incidence of dementia and mild cognitive impairment

OBJECTIVE

A history of depression has been linked to an increased dementia risk. This risk may be particularly high in recurrent depression due to repeated brain insult. We investigated whether there is a dose-dependent relationship between the number of episodes of elevated depressive symptoms (EDS) and the risk for mild cognitive impairment (MCI) and dementia.

METHODS

A total of 1,239 older adults from the Baltimore Longitudinal Study of Aging were followed for a median of 24.7 years. Diagnoses of MCI and dementia were made based on prospective data. Participants completed the Center for Epidemiologic Studies Depression Scale at 1- to 2-year intervals and were considered to have an EDS if their score was > or = 16. Kaplan-Meier survival curves, log-rank test for trend for survivor functions, and Cox proportional hazards models were conducted to examine the risk of MCI and dementia by number of EDS.

RESULTS

We observed a monotonic increase in risk for all-cause dementia and Alzheimer disease as a function of the number of EDS. Each episode was associated with a 14% increase in risk for all-cause dementia. Having 1 EDS conferred an 87%-92% increase in dementia risk, while having 2 or more episodes nearly doubled the risk. Recurrence of EDS did not increase the risk of incident MCI.

CONCLUSIONS

Our findings support the hypothesis that depression is a risk factor for dementia and suggest that recurrent depression is particularly pernicious. Preventing the recurrence of depression in older adults may prevent or delay the onset of dementia.

Depressive symptoms and risk of dementia: the Framingham Heart Study

OBJECTIVES

Depression may be associated with an increased risk for dementia, although results from population-based samples have been inconsistent. We examined the association between depressive symptoms and incident dementia over a 17-year follow-up period.

METHODS

In 949 Framingham original cohort participants (63.6% women, mean age = 79), depressive symptoms were assessed at baseline (1990-1994) using the 60-point Center for Epidemiologic Studies Depression Scale (CES-D). A cutpoint of > or = 16 was used to define depression, which was present in 13.2% of the sample. Cox proportional hazards models adjusting for age, sex, education, homocysteine, and APOE epsilon4 examined the association between baseline depressive symptoms and the risk of dementia and Alzheimer disease (AD).

RESULTS

During the 17-year follow-up period, 164 participants developed dementia; 136 of these cases were AD. A total of 21.6% of participants who were depressed at baseline developed dementia compared with 16.6% of those who were not depressed. Depressed participants (CES-D >/=16) had more than a 50% increased risk for dementia (hazard ratio [HR] 1.72, 95% confidence interval [CI] 1.04-2.84, p = 0.035) and AD (HR 1.76, 95% CI 1.03-3.01, p = 0.039). Results were similar when we included subjects taking antidepressant medications as depressed. For each 10-point increase on the CES-D, there was significant increase in the risk of dementia (HR 1.46, 95% CI 1.18-1.79, p < 0.001) and AD (HR 1.39, 95% CI 1.11-1.75, p = 0.005). Results were similar when we excluded persons with possible mild cognitive impairment.

CONCLUSIONS

Depression is associated with an increased risk of dementia and AD in older men and women over 17 years of follow-up.

Association of depression with subsequent mortality, cardiovascular morbidity and incident dementia in people aged 80 and over and suffering from hypertension. Data from the Hypertension in the Very Elderly Trial (HYVET)

BACKGROUND

depression is common in elderly people and may be associated with increased cardiovascular risk and incident dementia.

METHOD

participants in the Hypertension in the Very Elderly Trial (HYVET) completed a depression screening instrument, the Geriatric Depression Score (GDS), at baseline and annually. We examined the association of GDS score with incident stroke, mortality and dementia using Cox proportional hazards models (hazard ratios, HR and 95% confidence intervals, CI) adjusted for treatment group and other potential confounders.

RESULTS

2,656 HYVET participants completed the GDS. The mean follow-up was 2.1 years. A GDS score > or =6 was associated with increased risks of all-cause (HR 1.8, 95% CI 1.4-2.3) and cardiovascular mortality (HR 2.10, 95% CI 1.5-3.0), all stroke (HR 1.8, 95% CI 1.2-2.8) and all cardiovascular events (HR 1.6, 95% CI 1.2-2.1). Risk of incident dementia also tended to be increased (HR 1.28, 95% CI 0.95-1.73). Each additional GDS point at baseline also gave rise to a significantly increased risk of fatal and non-fatal cardiovascular events, all-cause mortality and dementia.

CONCLUSION

there was a strong association between baseline depression scores and later fatal and non-fatal cardiovascular endpoints over a mean follow-up of 2 years in a hypertensive very elderly group. The mechanism of this association warrants further study.

Moderating effect of apolipoprotein genotype on loneliness leading to depressive symptoms in Chinese older adults

OBJECTIVE

Depressive symptoms, which are both common and heritable, are important indicators of the extent of general well-being and health in old age. Identifying risk factors for depressive symptoms may lead to improved intervention and effective prevention. Both the presence of the apolipoprotein (APOE) genotype and loneliness are associated with later life symptoms of depression, and all three share a neuroendocrine signature, namely altered activity in the hypothalamic-pituitary-adrenal axis. The authors expected a positive association of loneliness with depressive symptoms, a negative link between APOE epsilon2 with depressive symptoms, and a significant genotype-environment interaction between loneliness (the social environment) and APOE epsilon2 on symptoms of depression.

DESIGN

This was a cross-sectional observational study.

SETTING AND PARTICIPANTS

A population-based sample of 979 Chinese people from Taiwan aged 54 years and older was examined.

MEASUREMENTS

A short-form of the Center for Epidemiologic Studies of Depression Scale was used and the genotype of APOE was obtained.

RESULTS

The interaction between loneliness and APOE epsilon2 was found to be negatively associated with depressive symptoms in adjusted regression models. Loneliness was also positively correlated with symptoms of depression.

CONCLUSIONS

These data suggest that the APOE epsilon2 genotype decreases vulnerability to symptoms of depression in the presence of a social stressor, namely loneliness in this case, and has implications for the enhancement of well-being among older adults. Future studies are needed to delineate the mechanism underlying this gene-environment interaction.